System and process of vector propulsion with independent control of three translation and three rotation axis

ABSTRACT

The present invention relates to a propulsion system of a vertical takeoff and landing aircraft or vehicle moving in any fluid or vacuum and more particularly to a vector control system of the vehicle propulsion thrust allowing an independent displacement with six degrees of freedom, three degrees of translation in relation to its centre of mass and three degrees of rotation in relation to its centre of mass. The aircraft displacement ability using the propulsion system of the present invention depends on two main thrusters or propellers and which can be tilted around pitch is (I) by means of tilting mechanisms and, used to perform a forward or backward movement, can be tilted around roll axis (X) by means of tilting mechanisms and, used to perform lateral movements to the right or to the left and to perform upward or downward movements (Z), the main thrusters being further used to perform rotations around the vehicle yaw axis (Z) and around the roll is (X). The locomotion function also uses one or two auxiliary thrusters or propellers and mainly used to control the rotation around the pitch axis, these thrusters or propellers and being fixed at or near the longitudinal is of the vehicle, with there thrust perpendicular or nearly perpendicular to the roll and pitch axis of the vehicle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. national stage filing under 35 USC §371 ofInternational Patent Application No. PCT/PT2006/000026 filed on Nov. 2,2006.

FIELD OF THE DISCLOSURE

The present invention relates to a propulsion system for a verticaltake-off and landing aircraft or vehicle capable of moving in any fluidor vacuum, more specifically it refers to a system of vector propulsionthrust control allowing independent movement with six degrees of freedomi. e. three degrees of translation in relation to its centre of mass orgravity and three degrees of rotation in relation to their centre ofmass.

The motion ability of the aircraft depends on two main thrusters orpropellers 3 and 4 which can be tilted around the pitch axis (Y) bymeans of tilting mechanisms 7 and 8, used to perform a forward orbackward movement, that can also be tilted around the roll axis (X) bymeans of tilting mechanisms 7 and 8, used to perform a right or leftmovement and, to perform upward or downward movement (Z) by increasingor reducing thrust, the main thrusters being further used to performrotation around the vertical axis (Z), and around roll rotation (X). Thelocomotion function also uses one or two auxiliary thrusters orpropellers 11 and/or 12, used mainly to control the rotation around thepitch axis (y), these auxiliary thrusters or propellers 11 and/or 12being able to be fixed or tiltable around one or two axis, roll andpitch axis.

The aircraft also includes control means having the ability to read allspatial and position parameters of the vehicle internal components(including the aircraft mass centre position 15) and other parametersthat are processed using the internal control algorithm in order tomaintain the user requested spatial orientation despite the existence ofexternal forces like gust winds and turbulences, by using the propulsionsystem ability to control independently six degrees of freedom, thuscountering any external force acting on the vehicle.

This invention is applicable to an aircraft, a space vehicle, a vehiclemoving in a fluid medium, such as a submarine, a ROV (Remotely OperatedVehicle) or to an UAV (Unmanned Air Vehicle). It is also applicable to atoy in any of the aforementioned embodiments.

BACKGROUND OF THE INVENTION

Over the years a lot of different VTOL (Vertical Take off and landing)configurations where tested. These configurations can be seen in, SethB. Anderson, “Historic Overview of V/STOL Aircraft Technology,” NASA™81280, March 1981 (the site http://www.aiaa.org/tc/vstol/wheel.html asone copy of the implementation wheel of V/STOL aircrafts).

Most of these configurations were never used in commercial aircrafts.The different configurations can be classified in several possible ways,such as:

-   -   Same propulsion for hover and flight    -   Different propulsion for hover and flight    -   Augmented propulsion power for hover

Each of these can be further divided in several subclasses like forexample, wing Tilt, propeller tilt and so on.

The classification wheel does not include the helicopter. The helicopteris also a VTOL machine since it can also take off and land vertically,the difference to the VTOL wheel aircrafts being that the helicopterdoes not have fixed wings for providing all (or most) of the lift forcefor the aircraft when it moves forward.

Among all of these VTOL machines the helicopter (in all its differentpropulsion versions) is clearly the best commercial VTOL machine and themachine with more units throughout the world.

Among all the tested VTOL configurations merely five exist at present,most of them only in a military configuration, and these are as follows:

-   -   Helicopter (all versions included have the same propulsion for        vertical and horizontal flight, with rotors),    -   the military Osprey V22 aircraft (same propulsion for vertical        and horizontal flight, with tilt rotors),    -   the military jet Harrier (same propulsion for hover and flight,        with vector thrust),    -   the military jet Yakovlev YAK-3B (different propulsion for hover        and flight), and    -   the military jet Lockheed Martin X-35 (with a thrust increase        system for hover, using a separate fan for VTOL operation).

Among these commercial airplanes it can be easily seen that the onlycivil VTOL aircraft is the helicopter. In the near future theconvertible Bell Augusta BA609, which is similar to the Osprey V22, willbe certified.

There is a number of reasons for the lack of success of most of thetested configurations for a VTOL aircraft, some of the reasons being:Very difficult control of take off and landing, very difficult controlof the transition phase from horizontal to vertical flight, high costand complexity, instability problems, large weight of several enginesfor horizontal and vertical flight and large weight of large shafts andgears, slow controls response time (aggravating instability),transmission failures, very high vibration and so on.

Among the enumeration of the problems of VTOL aircrafts it can be seenthat a large portion of the problems is related to control.

Normal aircrafts, from an aerodynamic control point of view, can beclassified in regard to their independent control axis as:

-   -   One forward translation axis (power) and three rotation control        axis—conventional airplane    -   Three translation axis, up or down (power), forward or backward        and left or right (due to the cyclic pitch of the main rotor,        but some rotation occurring also in the pitch axis or in the        roll axis) and one rotational axis—Helicopter (all types        including the not so conventional with two main counter-rotating        rotors).

Both of these configurations are not able to perform an independentcontrol of three translation axes and three rotation axis.

Some built flying machines can, at least in theory, displace themselvesaccording to most of the three translation and three rotation axis.

Among the previously referred VTOL wheel some aircrafts, like theHarrier, can, in the take-off (or landing) phase perform one translationand two rotations (pitch and roll axis) but only for a very short time.

It was previously mentioned that the helicopter comprises threetranslation axis, but in the helicopter and similar flying machines thetranslational displacement affects one of the rotation axis and as aresult the translation displacements are not fully independent of therotation axes.

When moving forward the conventional helicopter rotates also around thepitch axis, this meaning that the translation axis is not fullyindependent of the rotation axis, making it impossible for thehelicopter to maintain the angle of the longitudinal axis with thehorizon when moving forward or backward.

The existing patents do not cover the aforementioned problems, or justmake some reference to them without proposing a feasible solution for afull vector three translational and three rotation axis control aircraftin a simple form.

In the case of spacecrafts there are solutions for this vector control,but the existing solutions are complex and demand large numbers ofisolated thrusters.

The theoretically simple solution is to use two thrusters at the samedistance symmetrically from Cg (Mass centre of aircraft) on the Y axis(lateral axis, right or left side), and two thrusters located on the Xaxis (front or back) and two more on Z axis. This configuration allowsfor a full vector aircraft control. However very costly because itrequires the use of six equal thrusters or propellers, when actuallymost of the time only two will be used.

Several of the existing patents do not cover the problems mentionedpreviously, or just refer to them without achieving a complete solutionfor a full vector control (three translational and three rotation axis),thus allowing the implementation of a control algorithm thatsignificantly increases the agility of the aircraft, spacecraft orvehicle moving in any fluid or vacuum, and reducing the externalinfluence due to turbulence disturbances acting on the aircraft, thusincreasing passenger comfort (in gust wind situations or others).

Patent U.S. Pat. No. 6,719,244 “VTOL AIRCRAFT CONTROL USING OPPOSEDTILTING OF ITS DUAL PROPELLERS OR FANS” is a system using only twopropellers counter-rotating without cyclic pitch-change using propellerstilting around two axis for counter acting the pitch axis change whenthe aircraft is moving forward. This cannot achieve full vector threetranslational and three rotational axes control.

Patent U.S. Pat. No. 6,607,161 “CONVERTIBLE AIRCRAFT WITH TILTINGROTORS” and similar patents U.S. Pat. No. 2,230,370 and U.S. Pat. No.2,702,168 are convertible aircrafts with only two opposed rotors thatonly tilt forward and backward but not laterally, like the presentinvention.

Patent U.S. Pat. No. 3,106,369 “AIRCRAFT AND METHOD OF OPERATING SAME”has some similarities to the two tiltable main rotors (with cyclicpitch-change) and a jet which helps controlling aircraft pitch. Again,the aircraft does not tilt the main rotors around two axes, only one,and for moving laterally it uses the cyclic pitch-change. This cannotaccomplish full vector three translational and three rotational axescontrol of the aircraft.

Patent U.S. Pat. No. 3,141,633 “TILT-WING AIRCRAFT” is a tilt wingaircraft and has a number of rotors on the wing with an additionallocated in the back for aircraft pitch control, it only moves the rotorsin one axis, and again it cannot accomplish a full vector aircraftcontrol.

Patent U.S. Pat. No. 6,708,920 “AIR VEHICLE” uses four main identicalfans that are tiltable around two axes (roll and pitch.) This differentfrom the present invention using two main thrusters or propellers orjets tilting around two main axes and two small auxiliary thrusters orpropellers or jets fixed in their rotation axes. Other differences arethe concern of patent U.S. Pat. No. 6,708,920 with the engine and fanshapes, positions and cooling thereof and not with the full vectorability (independent rotations of the vehicle are not predicted). Thepossibility to counteract gust and turbulences is not mentioned.

Patent U.S. Pat. No. 5,419,514 “VTOL AIRCRAFT CONTROL METHOD”, relatesto a method of increasing the stability of a VTOL, aircraft, not being afull vector control method.

Patent U.S. Pat. No. 6,808,140 “VERTICAL TAKE-OFF AND LANDING VEHICLES”has a similar configuration but the main thrusters are aided by vanesthat alter the air flow direction, and the main fans only rotate aroundthe pitch axis (from the partially vertical position to full horizontalposition parallel to flight direction). It cannot be full vector.

Patent U.S. Pat. No. 3,544,042 “AERODYNE WITH VERTICAL TAKE-OFF ORLANDING MEANS” uses a similar configuration but doesn't have auxiliarypropellers for additional control, therefore it cannot be full vector.

Patent U.S. Pat. No. 1,851,764 “AEROPLANE” is a similar configuration,in some aspects, the main propellers being rotatable around two axis butthese are always synchronized and cannot be tilted independently. Thispatent does not include auxiliary propellers or jets as the presentinvention.

Patent U.S. Pat. No. 6,892,980 “VERTICAL TAKEOFF AND LANDING AIRCRAFT”is, from a control point of view, similar to patent U.S. Pat. No.6,708,920 but uses only one turbofan engine that drives the four twoaxis tiltable propellers and it has wings making it a convertibleaircraft. The configuration described by this patent is a rectanglewhere the four tiltable propellers are placed in the corners. Thisplacement and the identical four propellers or fans differ from thepresent invention. Nowhere in the patent is referred the possibility tocounteract the influence of turbulence, thus allowing, the increase inpassenger comfort. The aircrafts control is made by propeller or fanrotation and not by RPM (rotations per minute) changes or changes in thepropeller pitch combined with the propeller or fans tilting, thisdiffering from the present invention.

The present invention is intended to solve the aforementioned problemsby using a propulsion central system according to claim 1. Theadditional embodiments will be apparent from the dependent claims.

SUMMARY OF THE INVENTION

This invention relates to an aerospace propulsion system with thecapability to independently control the movement according to threetranslational axes and three rotation axis, in relation to their masscentre or gravity centre, with six degrees of freedom.

More specifically the present invention is a propulsion system for avehicle moving inside a fluid or in vacuum with the capability to moveaccording to three independent translation axis and three independentrotation axis, the vehicle comprising at least two main thrusters,connected to the vehicle by attachment means comprising tiltingmechanisms and joining means, said tilting mechanisms being able oftilting the main thrusters around two axis, pitch and roll,independently from each other, characterized in that the geometriccentre of the arrangement of said tilting mechanisms is localized at orin close vicinity of the mass centre of the vehicle, and in that thevehicle has at least one auxiliary thrusters provided with attachmentmeans comprising independent tilting mechanisms and joining means,arranged to allow tilting around two axis, pitch and roll, the geometriccentre of the arrangement of the independently tilting mechanisms ofsaid main and auxiliary thruster(s) being located on the longitudinalaxis of the vehicle, and the vehicle being provided with control meansconfigured to control the thrusters and their corresponding tiltingmechanisms.

The present invention further relates to a process of propulsion for apropulsion system according to claim 1, for a vehicle able to moveaccording to three independent translation axis and three independentrotation axes characterized in that:

-   -   translational movements over the horizontal plan is obtained by        tilting all the tilting thrusters, around their tilt axis        perpendicular to the intended translational movement, and also        by changing the global thrust of the thrusters in such a way as        to maintain the vehicle altitude,    -   translational movement along the vertical axis is accomplished        by having all the tilting thrusters in the vertical tilt        position by increasing the thrust of all the thrusters so that        the overall thrust is bigger than the vehicle weight in order        for the vehicle to ascend and reducing the thrust to less than        the vehicle weight for the vehicle to descend,    -   rotation around the vertical axis is done by tilting the        tiltable thrusters around the axis connecting these tilting        mechanisms, at equal angle of a tiltable thrusters in relation        to its opposed tiltable thrusters, in modulus, but with opposite        signal, and also by changing the thrust to maintain altitude,    -   rotation around the axis defined by the attachment means of the        tilting mechanisms of two main thrusters is accomplished by        changing the thrust in the auxiliary thruster(s), and using a        thrust perpendicular to the axis joining the tilting mechanisms,        the main thrusters tilting in the opposite sense to that of the        rotation of the vehicle and by also changing the thrust of the        thrusters in order to maintain altitude,    -   rotation around the axis orthogonal to the previous axis and the        vertical axis is done by a different thrust in the main        thrusters and by tilting the same in the sense opposite to the        vehicle rotation and also by changing the thrust of the        thrusters in order to maintain altitude,        and wherein, in the event of using propellers, these are placed        in opposition, the propellers turning in counter rotation in        order to compensate the torque adding on the vehicle.

The present invention further relates to the use of the aforementionedpropulsion system and propulsion process in aircrafts or spacecrafts orany other vehicle moving inside a fluid or in vacuum.

The preferred embodiments of the present invention are set forth in theaccompanying claims.

The translational axis, as set forth in the present invention, are:front or back, right or left and up or down; the rotational axis as setforth in the present invention are: vertical, longitudinal (roll) andlateral (pitch).

It is to be understood that, except otherwise stated, the word thrusterwill designate a thruster, for instance a rocket or ionic engine orsimilar, that generates thrust or a propeller or a shrouded propeller.

It is to be understood that the term aircraft, in the context of thepresent invention application, refers to any vehicle moving inside anyfluid or vacuum, except if otherwise indicated.

It is to be understood that, in the context of the present inventionapplication, when the aircraft uses propellers, each one is rotated byat least one independent engine.

It is to be understood that, in the context of the present inventionapplication, one aircraft comprises three axes (that run through themass centre), the longitudinal axis (roll), the lateral axis (pitch),and the vertical axis, these axis being orthogonal between them. Theroll axis of the aircraft is parallel to the standard direction(translational) of the movement (forward or backward) of the aircraft,the lateral (pitch) axis is perpendicular to the roll axis and formswith it a spatial plan that is parallel to the plan where the pilots siton, and the vertical axis is orthogonal to the other two axis.

It is to be understood that, in the context of the present inventionapplication, the front or frontal part of the aircraft is the part thatis located in the longitudinal axis furthermore from the mass centre inthe direction of the pilot eyes.

The rear is the part that is located on the longitudinal axisfurthermore from the mass centre in the inverse direction of the frontalpart.

The distance between the front and the rear is the length of theaircraft.

It is to be understood that the expression “near the mass centre”, inthe context of the present invention application, means that thelocation is at a distance between zero and twenty per cent of the lengthof the aircraft, except otherwise mentioned.

It is to be understood that “tiltable thruster” consists of any thrusterthat has a tilt mechanism allowing its tilting around two axis, roll andpitch.

It is to be understood that “opposite tiltable thruster” refers to thetiltable thruster on the other end of the line that passes through thetilting mechanisms of both tiltable thrusters.

It is to be understood that, in the context of the present inventionapplication, the main thrusters are always tiltable around two axis,roll and pitch, the axis connecting their tilting mechanisms passes ator in close vicinity of mass centre of the vehicle and they alone can,in the event of the vehicle being under the gravity of a body, like theearth, lift the vehicle. In the event where the aircraft is a spacecraftor a submarine (in this case the impulsion force of the water equals theweight of the vehicle), then the main thrusters are the ones thatproduce more thrust, and that the axis connecting their tiltingmechanisms passes at or in close vicinity of the mass centre.

It is to be understood that, in the context of the present inventionapplication, the auxiliary thrusters are the remaining thrusters.

The movement along all the axis of the vehicle is computed by aninternal controller (or controllers) that receives all the necessaryparameters, and also the user commands, and calculates, using itscontrol algorithm, the necessary action to act on the engines and on thetilt axis of the main thrusters, pitch and roll to be able to follow theuser commands counteracting the external aerodynamic perturbations, thusincreasing the passengers comfort. This is a big improvement to thepassengers, since in the event of external turbulent winds the presentinvention considerably reduces the passenger's discomfort.

The aircraft can, for example, move forward or laterally maintaining thelongitudinal axis of the aircraft unchanged relatively to the horizon(not possible for a conventional or less conventional helicopter).

The invention operates in the following manner in the event of theembodiment with two main thrusters and two auxiliary thrusters mountedat the front and rear of the vehicle:

The main thrusters can rotate (tilt) around the pitch and roll axis andare counter rotated with equal RPM, this minimizes the overall moment inthe aircraft as well as the gyroscopic forces on the aircraft.

The two main thrusters are mounted in such a way that they can rotatearound the pitch axis from the vertical (propeller axis) position to thehorizontal position (normal case, plus or minus ninety degrees, but itcan be more or less), this allows the forward or backward motion. Thistilt can be simultaneous or independent. If the propellers are tiltedsimultaneously (pitch axis) producing forward movement, the aircraftincreases the RPM or the propellers pitch angle in order to maintain theaircraft altitude.

The main thrusters can also rotate laterally (roll axis) synchronized orindependently. This synchronized tilt allows lateral motion, left orright, the RPM or the propellers pitch angle being increased to maintainaltitude.

The main thrusters can also tilt symmetrically in opposition to eachother around the pitch axis, leading the aircraft to rotate around thevertical aircraft axis (yaw), increasing simultaneously the thrust orRPM or changing the propellers pitch angle to maintain altitude.

The upward or downward movement is made by simultaneously increasing orreducing the thrust of the thrusters, in the event of using propellersby increasing RPM in fixed pitch propellers or by increasing pitch anglein variable pitch angle propellers.

The main thrusters can also rotate in both pitch and roll axes allowingthe vehicle to move diagonally and in order to maintain altitude the RPMis increased in fixed pitch propellers or by increasing pitch angle invariable pitch angle propellers, and if the pitch angle of the thrustersis different, the aircraft can at the same time rotate around the yawaxis (some movements may need to be stabilized through the auxiliarypropellers). If at the same time the power is increased sufficiently inboth thrusters and propellers, then the aircraft also moves in theupward direction.

The main thrusters can also be used with different thrusts on left andright thrusters or propellers in order to perform a rotation around thelongitudinal axis (roll) of the vehicle, but they have to be tiltedaround pitch axis (the rotation can be different) in order to compensatethe moment (yaw axis torque) induced on the vehicle by the differentthrust forces on each main thruster. In the event of the right propellerincluding another one rotating in its axis with equal angular momentumbut rotating in the opposing sense, and a similar situation occurs inthe main left propeller, then it is not necessary to change the pitch inorder to obtain a roll rotation.

The auxiliary thrusters are used for two main reasons:

-   -   Independent control of the pitch axis of the aircraft (changing        thrust force by changing thrusters thrust or by changing RPM or        the pitch angle of the front propeller in relation to the back        propeller); in this case some compensation of the torque on the        yaw axis has to be made by the main propellers and also it is        necessary to compensate the tilt around the pitch axis of the        main propellers so as to maintain the aircraft, if required,        with the same altitude relative to the ground; if each thruster        has two counter rotating propellers with individual absolute        torque then this compensation is not needed.    -   Compensation of the moment induced by the main propellers if        their resultant thrust axis is not fully aligned with the Cg        (gravity centre).

The system has a simple independent control to perform upward ordownward motion, lateral motion and forward or backward motion, and alsorotation around the vertical axis (yaw).

The independent control of the pitch and roll angles is more complicatedsince it requires the main thrusters and the auxiliary thrusters to beinvolved in a more complex control system (if each propeller is notdouble counter rotated and with same absolute torque).

The invention can also be used in a VTOL aircraft configuration in aconvertible form, with tandem wings (wings that produce lift force bothin the back and in the front) instead of a main wing like a conventionalconvertible aircraft such as the Osprey V22.

The present invention can be applied to a spacecraft, the thrustersbeing rocket engines or ion engines or any other suited thruster types.The invention can also be applied to an aircraft, but it can also beapplied at any other vehicle moving in a fluid, such as water.

The present invention can be applied to the propulsion system of asubmarine or a submarine ROV (remote operated vehicle), it can beapplied to an airship, it can also be applied to a toy moving inside afluid (or vacuum) and to autonomous vehicles moving inside vacuum or anyfluid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective simplified bottom view of the main elements ofthe present invention in one preferred embodiment.

FIG. 2 is a perspective simplified bottom view of the main elements ofthe present invention in another preferred embodiment, in which theauxiliary thrusters have two tilt axis.

FIG. 3 is a perspective bottom view, of another embodiment, with themain thrusters mounted together at the rear (or at front) of thevehicle, where one of them produces upward force and the other downwardforce.

FIG. 4 is a simplified view of the aircraft in the preferred embodimentof FIG. 1 in a takeoff or landing configuration (up, down translationalaxis).

FIG. 5 is a simplified view of the aircraft in the preferred embodimentof FIG. 1 moving forward (forward, backward translational axis).

FIG. 6 is a simplified view of the aircraft in the preferred embodimentof FIG. 1 moving sideways (right side, left side translational axis).

FIG. 7 is a simplified view of the aircraft in the preferred embodimentof FIG. 1 performing a rotation around to the vertical axis.

FIG. 8 is a simplified view of the aircraft in the preferred embodimentof FIG. 1 performing a rotation around the lateral (pitch) axis.

FIG. 9 is a simplified view of the aircraft in the preferred embodimentof FIG. 1 performing a rotation around the longitudinal (roll) axis.

FIG. 10 is another simplified embodiment with only one thruster asauxiliary thrust unit.

FIG. 11 is a simplified bottom view representation of anotherembodiment.

FIG. 12 is a simplified view of the preferred embodiment of FIG. 1applied to an aircraft.

FIG. 13 is a simplified view of another embodiment applied to anaircraft, with two front auxiliary thrusters and two rear thruster.

FIG. 14 is a simplified top view of the preferred embodiment of FIG. 1applied to a convertible aircraft with wings.

FIG. 15 is a simplified top view of the embodiment of FIG. 11 applied toan aircraft.

FIG. 16 is a simplified top view of the embodiment of FIG. 11 applied toan aircraft with wings with conversion capability.

FIG. 17 is a simplified view of the diagram of the aircraft control.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the preferred embodiment, the present invention comprises twothrusters designated as main thrusters, that are independently moved (byany kind of engine) and are counter rotated, and which are placedlaterally in the aircraft, with independent thrust variation or RPMvariation or propellers pitch change (they can however be synchronized),being tiltable around two axis, positioned in such a way that theirresultant thrust force, in all the possible configurations of theaircraft (take off, landing and horizontal flight), passes at or inclose vicinity of the Cg, in the event of equal tilt and equal RPM orpropellers pitch angle. There are also provided two thrusters orpropellers (moved by any kind of engine) counter rotated, withindependent control of thrust or RPM or propellers pitch change (theycan however be synchronized), placed at the front and at the rear of theaircraft, these being fixed (not tiltable). In other variation of thisembodiment these auxiliary thrusters or propellers also comprise twotilt axis (or one tilt axis), like the main thrusters. These thrustersare referred as auxiliary thrusters.

In the preferred embodiment, the roll axis of the aircraft comprises inits proximal end (or in close vicinity) one auxiliary thruster and inthe other near (or in close vicinity) the other, the two auxiliarythrusters not being able to tilt, and when their propulsive force isidentical, the resultant of the forces on the auxiliary thrusters passesat or in close vicinity of Cg. To perform a forward movement theaircraft moves in the same direction of the roll axis.

In the preferred embodiment, the aircraft uses independent engines foreach one of the propellers connected directly to the propellers shaftwithout transmission gears, like for example the Osprey V22, so as toreduce weight of the aircraft.

The structural support of the main engines is calculated to resist theforces created by the rotation of the engines (rotating masses andgyroscopic effects and airflow interactions). The engines and movingstructures (like fans or propellers) are as light as possible. Thisallows for the control speed of the thrusters (roll and pitch) to bevery fast, which in turn allows enough time for the aircraft controlsystem to calculate a counter action (which includes the main thrustersand auxiliary thrusters) in the case of external turbulence or gustwind, this diminishing the internal random accelerations and increasingthe passenger and pilot comfort.

The main thrusters are tiltable around the pitch axis by an electricaldrive engine (or other mechanical drive system), the same applying forthe roll tilt. The electrical drive engines are fed by generatorsmounted in each explosion engine.

In the preferred embodiment the auxiliary thrusters are fixed (cannottilt like the main thrusters) only the thrust or the RPM or thepropeller pitch angle being controlled, end they are located at themaximum possible distance from the Cg (on the longitudinal axis of theaircraft) to minimize the size and power requirements of the engines.This assures the maximum possible aircraft pitch control action.

In the preferred embodiment the main thrusters are propellers withinternal tiltable fans, thus increasing the static thrust, when comparedwith a single propeller, the same configuration being used for theauxiliary propulsion system. The propulsion can also use only propellersor even sophisticated augmented thrust propulsion systems like the onedescribed in U.S. Pat. No. 4,796,836 or any other.

The engines for the propellers (main and auxiliary) can be independentelectrical or explosion engines (two or four strokes or rotative), orturbines or any other rotating engine.

The present invention, in any of the aircraft embodiments, can be usedin two different forms:

-   -   Vector without wings    -   Vector with wings (convertible VTOL aircraft)

In the vector without wings mode, the present invention has noautorotation capability because of the small size of the propellers, butsafety is assured by the use of a ballistic parachute for the wholeaircraft, and in the version with electrical engines, since eachpropeller uses several electrical engines, this allows the normalpropeller function through power compensation of the remainingelectrical engines (this can also be achieved by other engine types).

If one of the main independent engines fails, the aircraft electroniccontroller automatically shuts down the working engine (to avoidrotation around the yaw axis and the roll axis) and automatically theparachute is deployed, this parachute being also able to be activatedmanually.

The aircraft, on the preferred embodiment, in the vector with wingsversion has fixed wings in a tandem wings configuration (wings thatproduce lift at the front and back of airplane) to allow it to work as aconvertiplane aircraft. In this configuration the aircraft, in asimplified version, does not use conventional airplane controls like theailerons, it uses only the two main thrusters and the two auxiliarythrusters to provide all the required control (again there are threetranslational axes and three rotational axes control).

The aircraft, in a simplified version, comprises also control of therudder, in a more complete (and expensive) version the aircraft cancomprise full airplane controls and also the full vector control alreadydescribed.

The controller of the aircraft can be a single one, or three or moreinvolved in a majority decision process. The controller reads all theneeded parameters such as, longitudinal axis position, vertical axisposition, lateral axis position, X (forward), Y (lateral), Z (up) speedsand accelerations, main thrusters, pitch and roll position, RPM or proppitch of auxiliary and main thrusters, velocity of external fluid,temperature, pressure, altitude, forces internal resultant and momentsand also the user input controls, it also computes at every instant theposition of the Cg.

The control algorithm is any that allows user control according to threetranslational axes and three rotation axis, minimizing externaldisturbances over the aircraft, like gust winds or aerodynamicturbulence.

In the event of full controller failure the electrical system canreceive the user commands directly and pass this information to the mainthrusters and auxiliary thrusters, but the aircraft looses the gust orturbulence resistance capacity because it cannot calculate the best wayto counteract the external turbulence. This security feature uses aswitch MANUAL/AUTO to change the mode from automatic control to manualcontrol, this characteristic being applied to all the embodiments of thepresent invention in the aircraft form.

Because of the counter rotation of the main and auxiliary propellers theaircraft is stable and easy to control even in manual mode.

The propellers for the first embodiment can be of any type with anynecessary number of blades. The propellers can be very simple, withfixed pitch or more complicated, with variable pitch, and can even havecyclic pitch.

The preferred embodiment can also use all the auxiliary thrusters withtilting capability in two axes, or just tiltable in one axis or fixed.

In another embodiment of the present invention the main thrusters arepositioned on the longitudinal axis and the secondary thrusters arepositioned on the lateral axis of the aircraft.

In this case the conversion to airplane mode is made by carrying out aninety degrees rotation on the axis connecting main engines. The rollaxis, in the airplane conversion mode will have two in-line (in theforward, backward direction) main thrusters.

In this embodiment it is possible to use only one thruster for theforward displacement, which is a much more stable configuration inairplane mode, in the event of one main engine failure. If used in aconvertible configuration it can use normal airplane wings (more or lesscentred in the aircraft longitudinal axis, near the Cg) with insidethrusters mounted near the end (or at the end) of the wings, performingthe same function of the auxiliary thrusters of embodiment one, but withcontrol for roll and pitch exchanged.

In another embodiment the aircraft uses only one auxiliary thruster,which can be placed at front or back of the aircraft, this auxiliarythruster having the capability to produce upward and downward forces (byrotating clockwise or counter-clockwise the propeller or by changing theprop pitch angle maintaining the same rotation direction), alternativelytwo propellers can be used for the auxiliary thruster, each rotating inopposing directions, one for the upward force and the other for thedownward force, with both props rotating in the same spatial axis. Theuse as a convertible is the same as the embodiment one in FIG. 1.

In all of the embodiments it is possible to use double propellers. Thismeans that each thruster moves two counter rotating propellers in thesame axis. This increases the aerodynamic efficiency and reduces theangular moment over the aircraft and the gyroscopic forces generated bythe tilt of the main engines.

All of the previous possible embodiments of the present invention canuse thrust augmentation devices such as the one described in patent U.S.Pat. No. 4,796,836.

Other embodiments are also possible with more than four main thrusterstiltable around the pitch and roll axis.

FIG. 1 is a view from below of the preferred embodiment in a simplifiedrepresentation.

With reference to FIG. 1 the axis (X) pertains to the forwardtranslation motion, axis (Y) is the lateral axis and (Z) is the upwardor downward translation axis. The (X) axis is parallel to thelongitudinal aircraft axis 14, the (Y) axis is parallel to aircraft mainthrusters support axis 13. The aircraft mass centre Cg is 15 and islocated at the intersection of the longitudinal aircraft axis 14 withthe lateral axis 13 (or in close vicinity).

In FIG. 1 supports 13 and 14 are a very simplified representation of theactual supports, intended for helping to understand the invention.

In FIG. 1 there are two main thrusters and these alone can lift theaircraft, and there are also two thrusters intended mainly for theaircraft pitch control.

In a implementation of the preferred embodiment of an aircraft, the mainpropellers are driven by two 48 Hp two stroke engines with 32 Kg weightand about 6200 RPM (maximum) commercially available from manufacturerSimonini. The engines comprising a reduction gear (belt) of 1:2.7 fordriving a 1620 mm diameter propeller. The engine and propeller assemblyhas a 1340N maximum lifting force. Through the use of shroud 1 thethrust of propeller 3 can be augmented. Shroud 2 also increases thetotal thrust of propeller 4. Propeller 3 rotates counter clockwise andpropeller 4 clockwise (as seen above). The total diameter of the shroudis 1900 mm. This leads to a very small sized aircraft. The example ofthe embodiment is designed to withstand a person weighing less than 100Kg for a maximum of three hours flight time.

The main engines can be different, like for example a light four strokesengine or an electrical one.

Item 7 is the two axis (pitch and roll) tilting mechanism for engine 5and propeller 3 and shroud 1. The tilt can be a tilt forward (on the Yaxis), to about 90°, or around the (X) axis. The two axis rotation tiltmechanism 7 uses two electrical engines, in present example a 40 Nmengine weighing 2.4 Kg is used in each tilt axis.

The right engine 6 is identical to engine 5 but rotates in the oppositedirection.

Shroud 2 increases the lift force in takeoff and landing situations. Thetilting mechanism 8 of engine 6 and their attached systems are alsomoved, by two electrical engines of 40Nm. The electric power for theaircraft and also for the electrical tilting mechanism comes fromgenerators (not shown on figures) attached on main engines. The tiltingmechanisms 7 and 8 each comprises two tilt axes (roll and pitch).

The front auxiliary propeller 11 also uses an increase thrust throughshroud 9, and in the back of the vehicle the same situation occurs, thistime for propeller 12 and shroud 10. The auxiliary propeller rotation offront prop 11 is counter-clockwise and the back propeller 12 clockwise(the rotation senses may be reverse, the same situation occurs for themain propellers).

The distance of the centre of the intersection of the roll and pitchaxes (About Cg) to each of the left and right tilting mechanism centreis 1.4 m (although it could be larger). The distance from Cg toauxiliary propeller axis is 1.5 m (can also differ in different aircraftversions). The auxiliary propellers are powered by electrical enginewith 1.5 KW power and 400 g weight delivering 70N thrust, the propellersare 380 mm diameter.

The structure of the aircraft, in the preferred embodiment, is madebased on support 13 of main thrusters. Support 13, in the presentexample, is of a dihedral shape in order to allow a bigger roll angle ofmain engines. The pilot is seated with is mass centre positioned at thesame (or in close vicinity) point of the Cg of the entire aircraft.

Because of the counter rotated propellers for the main and auxiliarypropellers the aircraft is much more stable than a conventionalhelicopter with just one main rotor. Because of this characteristiclearning to fly the vehicle is easy.

The aircraft comprises a low cost digital controller which takes thesensors readings and user commands and carries out the computation ofall the needed variables for the control of the main and auxiliaryengines and tilting systems.

The aircraft can move independently according to three translationalaxis, (X) forward or backward, (Y) right or left and (Z) upwards ordownwards. It has also the capability to move independently around threerotational axis, rotation around (Z) axis (yaw), rotation around (X)axis (roll) and rotation around (Y) axis (pitch). Due to this it is afull vector aircraft.

The FIG. 2 shows other embodiment in which the auxiliary thrusters alsotilt around two axis, roll and pitch. The front auxiliary thrustercomprising an engine 50 connected to the structure by 14 a, mechanism 61allowing tilting around two axis, the back thruster using engine 51, thetilt mechanism 60 allowing tilting around two axis, and being connectedto the structure by 14 a (simplified version).

The FIG. 3 is a perspective view from the bottom of another embodimentwith the auxiliary thrusters jointly placed on the longitudinal axis ofthe vehicle, in which thruster 11 produces upward force and thruster 12downward force (or the opposite). The thrusters can be located at therear or at the front in the longitudinal axis of the vehicle.

FIG. 4 shows the independent translational movement up or down in thepreferred embodiment of the FIG. 1.

With reference to FIG. 4 (X) is parallel to the forward or backwardtranslational axis, (Y) is parallel to the left or right aircraft axisand (Z) is parallel to the up or down axis of the aircraft. In FIG. 4there are four thrust forces (F1) from the left main thruster, (F2) fromthe right main thruster, (F3) from the forward auxiliary thruster and(F4) from the backward auxiliary thruster. These forces are in-line withthe (Z) axis, so total upward force is:Total Z force=F1+F2+F3+F4

This total force must be greater than or equal to the weight of theaircraft (W).

The aircraft moves only in the Z axis (if there are no outside wind orexternal forces). If total Z Force is greater than W (weight) theaircraft goes up and, if the Total Z force is less than W then theaircraft goes down. The moments affecting the aircraft are null becauseof the symmetry of all forces relatively to the Cg.

With reference to FIG. 5 the aircraft has both thrusters tilted aroundthe pitch axis (rotated to the front of the vehicle). Both mainpropeller axes are at an angle (a) with the (Z) axis. The conditions forthe vehicle to move forward (translation in X axis alone) are:

For the vertical Z componentF1 Cos(a)+F2 Cos(a)+F3+F4=W

But F1=F2 and F3=F4 so:2F1 Cos(a)+2F3=W

For the horizontal X component:Fx=F1 Sin(a)+F2 Sin(a)=2F1 Sin(a)

Fx=Forward motion force (X) axis

Because of the symmetry of all the forces in relation to the Cg of thevehicle, the moments affecting it are null.

The vehicle moves forward solely along the translation (X) axis if theupward forces are always equal to the Weight (W). Because of this whenthe main propellers tilt forward at the same angle (a) the RPM or thepitch change of the propellers are increased in order for the upwardforce to equal the weight of the aircraft.

The auxiliary thrusters maintain their forces, before and after the tiltmotion. But other ways to maintain solely (X) translation motion arepossible, (F3) and (F4) forces can also be varied and the thrust of themain engine can be slightly reduced, the condition being that the vectorsum of all forces acting on axis (y) equals the weight of the vehicle.

FIG. 6 is a simplified representation of the conditions for the aircraftto independently move laterally (Y axis translation) in the preferredembodiment of FIG. 1.

In this case, both main thrusters are again tilted around the roll axissimultaneously at the same angle, in this case angles (b1) and (b2)(b1=b2) to the vertical (Z) axis. The conditions for the aircraft tomove only in the (Y) axis are:

For Z axis: F1 Cos(b1)+F2 Cos(b2)+F3+F4=W

With F1=F2 and F3=F4 we have: 2F1 Cos(b1)+2F3=W

The motion force in Y axis will be: Fy=2F1 Sin(b1)

The moments affecting the aircraft are again zero. Basically for thevehicle to move solely along the (Y) axis the aircraft tilts both mainthrusters, around the roll axis, at the same angle and at same timeincreasing the RPM or pitch change so the (Fz) component remainsunchanged all the way through the tilting.

FIG. 7 is a simplified representation of the preferred embodiment ofFIG. 1, locating to rotation around the vertical axis (Z).

In this case the aircraft has both thrusters tilted around the pitchaxis, but the left thruster is tilted at angle (c) forward and the rightis rotated at angle (d) backward. The angles (c) and (d) are equal inmodulus but reverse in directions. The conditions for independentrotation over (Z) axis are:Fz=W=F3+F4+F1 Cos(c)+F2 Cos(d)

Usually F3=F4 and F1=F2 so:Fz=2F3+2F1 Cos(c)=W

The moment around Z axis is:Mz=2LF1 Sin(c)

L=Distance between Cg and the centre of thrust force (for example F1) ofone of the main thrusters.

Again, during the rotation around (Z) axis, the aircraft needs toincrease thrust or RPM or props pitch to maintain altitude.

FIG. 8 shows how the aircraft, in the preferred embodiment of FIG. 1,performs an independent rotation around (Y) axis (pitch).

For this movement the forces (F3) and (F4) of the auxiliary thrustersmust be different. This creates a moment around the (Y) axis. Tomaintain the aircraft altitude the following condition must be achieved:F3 Cos(h)+F4 Cos(i)+F1 Cos(e)+F2 Cos(g)=W=Fz

In this case F1=F2 and angle (h) is equal to angle (i).

This simplifies the previous formula:W=(F3+F4)Cos(h)+F1(Cos(e)+Cos(g))

For the aircraft not to move forward (or backward) another condition isneeded:(F3+F4)Sin(h)+F1(Sin(e)+Sin(g))=0=Fx

The moment around Y axis is My=SF3+SF4=S(F3+F4)

S=Length from Cg to centre of thrust of one of the auxiliary propellers,is assumed as being equal in the case of both auxiliary thrusters.

The yaw moment is:F1 Sin(e)+F2 Sin(g)=Mz

Mz=Moment in (Z) axis, because of the different moments caused by theauxiliary propellers.

The moment around the aircraft longitudinal axis (XI) must be zero, so:Mx1=LF1 Cos(h+e)+LF2 Cos(g+h)=0

All other forces and moments are zero.

FIG. 9 shows the last independent axis movement, in this case therotation around (X), (X) being the roll axis of the aircraft.

In order for the roll axis rotation of the aircraft to occur the thrustforce of main thrusters must not be equal, thus generating a rollmoment. This creates a (Z) axis moment (yaw), because of the differentforces (F1) and (F2), if the propellers are not double and withcompensated moments for each thruster, this yaw moment must becompensated. Also the axis of forces (F3) and (F4) rotate in space.

(F1′) is the projection of (F1) in the plane that passes through (Z) andthe lateral axis of the aircraft, (F2′) is the projection of (F2) in thesame plane.

The angles between the (Z) axis and (F1′) and (F2′), (i) and (k)respectively, are equal. The angles (o) and (q) are the angles between(F1) and (F1′), and between (F2) and (F2′).

The conditions for the aircraft to turn only around the roll axis are:F3 Cos(n)+F4 Cos(m)+F1 Cos(j)Cos(o)+F2 Cos(k)Cos(q)=W=Fz

With F3=F4 and equal angles (n) and (m).2F3 Cos(n)+F1 Cos(j)Cos(o)+F2 Cos(k)Cos(q)=W=Fz

Another condition is that the force on the lateral axis is 0:2F3 Sin(n)+F1 Cos(o)Sin(j)+F2 Cos(q)Sin(j)=0And: Fx=F1 Sin(o)+F2 Sin(q)=0

Because angles (p) and (n) are equal, for the moments we have:Mx=LF1 Cos(j+n)Cos(o)+LF2 Cos(j+n)Cos(n)My1=S(F3+F4)=0

The moment on Z is:Mz=LF1 Cos(j)Sin(o)+LF2 Cos(j)Sin(q)=0

This is a more complicated case than the previous ones, but it provesthat it is possible to make an independent rotation around the (X) axis,F1 being able to be used as a predefined function of F2.

The preferred embodiment comprises several safety features, the main onebeing the use of a ballistic parachute (not shown in the figures) forthe entire aircraft that works well in the case of a fall at more than30 m above ground level. In this example of the preferred embodiment thechute weighs just 6 Kg and can withstand an aircraft with 340 kg. Allembodiments of present invention use this safety feature.

Because of the small size of the propellers the aircraft cannot carryout an autorotation in the event of engine failure. Because of this,when one of the main engines fails, the aircraft automatically turns offthe other main engine. This action minimizes the rotation around (Z)axis and also (X) axis if one engine remains at work. After shuttingdown the remaining engine the aircraft deploys the ballistic parachute,this operation also being able to be pilot controlled.

The preferred embodiment can be done in a hybrid version, which uses oneexplosion engine (Ecofly with 100 Hp and about 65 Kg) to drive tenelectrical engines Predator Plettenberg used as electrical generators tosupply electrical power to five electrical engines per main propeller.These electrical engines are identical to the generators because therebrushless and they weigh 1.5 Kg and can output 10 KW. The auxiliarypropellers are moved by the same engines as the previous version or bythe Predator engines. This is also a version for one pilot with about100 Kg maximum, this version being able to have maximum weight of 320Kg. This version has the significant advantage that in the event of thefailure of one electrical engine the other four engines can keep theaircraft flying without any problems, this being a very effectivesecurity feature.

One other version of the first embodiment is the toy version. It usesfour GW/IPS-DX-1XCS electrical engines with propellers 10×4.7″ directand inverse, with two GWS PICO servos for each main propeller tilt andone (or two) GWBPA001 batteries. The toy weigh about 400 g. The toycontrol uses the control of FIG. 17 but only in the MANUAL mode, howeverit also can use a more efficient control.

FIG. 10 is another embodiment (simplified version of first embodiment).Again (X) is the forward axis, (Y) the lateral axis and (Z) the verticalaxis of the aircraft. This embodiment comprising only one auxiliarythrust device, this being in fact the most simple embodiment of thepresent invention, the auxiliary shroud 9 and the auxiliary propeller 11(can produce upward force (F3) or downward force (F4) by pitch change)the left main shroud 1 and the left main propeller 3 produce liftingforce (F1), the right main shroud 2 and the right main propeller 4produce lifting force (F2), the weight (W) is applied at the Cg (notshown), 14 is the longitudinal aircraft support, simplified in order tobetter explain the invention.

The upward and downward forces on the auxiliary thrusters are obtainedthrough the use of two electric engines (or other kind of engines) thatdrive two independent propellers, one in the clockwise direction and theother in the counter clockwise direction, or alternatively just oneengine and a single propeller with enough pitch change capability toproduce sufficient upward or downward forces (maintaining the samerotation direction).

FIG. 11 is a perspective bottom view of one embodiment of present theinvention, the (X) axis is the forward axis (longitudinal axis), the (Y)axis is the lateral axis and the (Z) axis is the vertical axis of theaircraft. In this embodiment the aircraft is rotated 90° around thevertical axis relatively to the preferred embodiment. The aircraftcomprises a fontal shroud 1 with its propeller 3 rotating in an oppositedirection of propeller 4 inside back shroud 2. Engine 5 rotatespropeller 3 and is tilted around two axis, pitch and roll, by tiltingmechanism (not shown in detail) 7, engine 6 rotates propeller 4 and isalso tilted around two axis, pitch and roll, by tilting mechanism 8.Both thrusters have enough thrust capability to lift the aircraft. Themain thrusters and engines and tilting mechanisms are supported by rod13 which passes through (or at close vicinity of) Cg, at a cross anglewith the support 14 for the auxiliary thrusters. On the left side of theaircraft there is provided a shroud 10 with its propeller 12 and on theright side the auxiliary shroud 9 and propeller 11. The aircraftoperates in the same manner as the preferred embodiment but with twoaxis exchanged (X) and (Y).

FIG. 12 is a top view of the present invention's preferred embodiment ofFIG. 1 applied to an aircraft. (X) is the forward axis, (Y) the lateralaxis and (Z) the vertical axis. Left shroud 1 has propeller 3 driven byengine 5, the right shroud 2 uses propeller 4 driven by engine 6, thetilting mechanisms are not visible in FIG. 12. The front auxiliarythruster is item 11 and the back auxiliary unit is item 10. Theauxiliary units are placed at the maximum distance from Cg (not shown inFIG. 12) in order to maximize moment around (Y) axis (pitch). Theaircraft comprises a structural support 13 to support the main units, atthe back there is provided a right horizontal stabilizer 30 and a lefthorizontal stabilizer 31, a vertical stabilizer 32 and a rudder 33. Inthis configuration the aircraft has three independent axis translationalcontrol and three independent axis rotational control and also usesrudder control. The occupant, in the present version, sits on 34 withits Cg placed at the aircraft Cg or in close vicinity. With more poweron the main and auxiliary units more load capacity is possible.

One additional safety feature of the complete aircraft is the ruddercontrol. This helps the yaw control axis.

FIG. 13 shows another embodiment of present invention, in which each ofthe auxiliary thrusters is double and is placed symmetrically to theaircraft roll axis.

The aircraft is provided, at the front, with the auxiliary thrusters 11a and 11 and in the back with the auxiliary thrusters 10 and 10 a, andeverything else in this embodiment is identical to the embodiment ofFIG. 10.

FIG. 14 is the plan view of the embodiment of FIG. 1 of the presentinvention applied to a convertible aircraft. Because of the centralposition (or in close vicinity) of the Cg and also of the centralposition of the main propulsive units, the aircraft uses an unusualtandem wings configuration. In this case the front wings are placedbelow the back wings, (the reverse is also possible) which are mountedon top of the vertical stabilizer of the aircraft, this decreasing thethrusters interference in the wings.

The aircraft uses left shroud 1 and propeller 3, which is driven byengine 5, to produce the left thrust and shroud 2 and propeller 4,driven by engine 6, to produce the right thrust, both main units beingsupported by structure 13. The main units can be tilted around pitch androll axis by their tilting mechanism (not shown on FIG. 14). Theaircraft comprises a front auxiliary thruster unit 9 and a backauxiliary thrust unit 10.

Main units can be tilted at least 90° around the pitch axis (forward)for the aircraft to operate as a normal airplane. The front wing 41 andthe back wing 40 can produce all the thrust needed for the vehicle to beairborne and performing a horizontal displacement when its speed isenough, 34 is the occupants space.

The aircraft control in helicopter and airplane mode is always done bythe full vector control, and in the airplane mode it uses also rudder 33attached to vertical stabilizer 32 to improve the yaw control.

The aircraft can also have, in more elaborate versions, full airplanecontrol surfaces.

FIG. 15 is the top view of the embodiment of FIG. 11 applied to anaircraft. In FIG. 15 the main thruster are placed at front and back ofthe aircraft and the auxiliary ones laterally. Shroud 1 comprisespropeller 3, which is rotated by engine 5, these front unit beingsupported by structure 13 a. At the back there is provided a shroud 2which has a propeller 4, rotated by engine 6, this unit being supportedby 13 b. The left auxiliary unit uses propeller 12 and the rightauxiliary unit uses propeller 11, both being supported by 14. Theaircraft comprises a horizontal stabilizer 30 and a vertical stabilizer32 attached to rudder 33. The rudder is an independent control (but canbe used in conjunction with the yaw control by the aircraft maincontroller). The motion control is the same as in the preferredembodiment with the controls for lateral rotation performed by the mainunits whilst the controls for the longitudinal roll are performed byauxiliary units.

FIG. 16 is a top view of the embodiment of FIG. 11 as a convertible, inairplane mode. The main units are placed in the front of the aircraft.In this configuration the aircraft comprises central wings 40 (likenormal airplanes). The auxiliary units are located at the end (or inclose vicinity) of the wings, left auxiliary unit 12 and right auxiliaryunit 11 are also located at the end (or in close vicinity) of the wings.Support 13 a of the front unit is mounted at the centre line of theaircraft and the support 13 b of the back main thruster unit is mountedbelow and has a rod connected thereto at in a right angle (not shown) inthe up direction, this allowing tilting of at least 90° of the backunit.

The airplane comprising a front thrust unit supporting structure 13 aattached to tilting mechanism 7 attached to front engine 5, whichrotates propeller (dashed lines) 3 inside shroud 1.

The back support 13 b supports the tilting mechanism 8 attached toengine 6 which rotates propeller 4 inside shroud 2. Occupants are placedat space 34, at the back of the aircraft there is the horizontalstabilizer 30 and vertical stabilizer 32 and rudder 33. The aircraftalso comprising, in more elaborate versions, full airplane controlsurfaces.

FIG. 17 is a block diagram representation of the controller system ofthe present invention in the Automatic/Manual selection part.

The controller has a MANUAL/AUTO 200 switch. In the normal AUTO LOposition switches 202 (from top to bottom of FIG. 17) are set to theCONTROLLER 203 position, so the controller 203 controls all the flightactuators in vector mode: front auxiliary unit RPM or propeller change“AUX L” 212, left main unit RPM or propeller pitch change “MAIN L” 213,Y tilt (roll) of left main unit “Act Y1” 214, left main X tilt (pitch)“Act X1” 215, right main Y tilt actuator “Act Y2” 216, right main roll Xtilt actuator “Act X2” 217, right main unit RPM or propeller pitchchange “MAIN R” 218 and back auxiliary unit RPM or propeller change “AuxR” 219.

The controller receives data from sensors 204 and the user commands X205, Y 206, Z 207, X aircraft rotation (roll) 208, Y rotation 209, Zrotation 210 and power 211. The controller uses these variables tocompute the necessary actuator controls when MANUAL/AUTO 200 is at AUTOposition.

In the event of a complete controller failure the user can set 200 toMANUAL position. In this position the commands to the actuators comedirectly (with simple arithmetic operations independent of the aircraftcontroller,) from user commands.

The X translation command goes to SUM block 222 and 223. In 222 the Xsignal is summed to the Z rotation command and in 223 subtracted by Zrotation command.

Output of 222 (X+Rotation Z) goes direct to “Act Y1” 214 and output of223 (X−Rotation Z) goes to “Act Y2” 216. The X translation and the Zrotation are assured.

The POWER 211 command is sent directly as sum input to sum blocks 220,221, 224 and 225.

The Y translation command is sent directly to “Act X1” 215 and to “ActX2” 217. Z command is not connected in MANUAL mode.

The X roll command is summed in 221 to the POWER signal, the output ofthe sum is then sent to “Main L” 213 RPM or pitch change control, X rollis also subtracted in 224 to the power signal, the output of thesubtraction is then sent to “MAIN R” 218 RPM or pitch change control.The Y rotation command is summed to the power signal in sum 220 whichconnects to “Aux L” 212 RPM or pitch change control, Y rotation commandis also sent to 225 (where it is subtracted to the power signal), andits output controls “Aux R” 219 auxiliary unit RPM or prop pitch change.

This implementation allows a perfect X, Y, Z translation control (withPOWER replacing Z command) and an also perfect Z axis rotation control.The X roll and Y pitch rotations are not perfect because the yaw moment(generated by the different Main RPM or the different auxiliary RPM) isnot compensated. Even so it is possible to get a reasonable Roll andPitch control of the aircraft in MANUAL mode.

It is to be understood that the present invention is not limited in itsapplication to the details of the construction and the arrangement ofthe components described in the description or in the drawings.

The invention is able to adopt other embodiments or of being implementedor carried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein are for the purpose ofdescription only and should not be regarded as limiting.

It should be appreciated that the one skilled in the art, taking intoaccount the teachings of the present invention, will be able to makenumerous variations, changes and equivalents without departing from thescope of the present invention as set forth in the claims.

The invention claimed is:
 1. A propulsion system connected to a vehicle,said vehicle able to move inside a fluid or vacuum with threeindependent translation axis movements and three independent rotationaxis movements, comprising at least two main thrusters, connected to thevehicle by means for attaching comprising tilting mechanisms and meansfor joining, said tilting mechanisms tilting the main thrusters aroundtwo axes, pitch and roll, independently from each other, wherein ageometric center of an arrangement of said tilting mechanisms is locatedat or in close vicinity of a mass center of the vehicle, and in that thesystem comprises at least one auxiliary thruster connected to thevehicle by the means for joining, wherein the at least one auxiliarythruster and the tilting mechanisms of the main thrusters define ageometrical figure shaped, approximately, as an equilateral triangle oras a diamond, said triangle or diamond lying on a horizontal plan,defined by longitudinal (roll) and lateral (pitch) axes of the vehicle,the at least one auxiliary thruster and the tilting mechanisms of thesaid main thrusters being disposed at apexes of said geometrical figurein such a way that the geometrical center of said figure is disposed ona longitudinal axis of the vehicle, wherein the at least one auxiliarythruster is fixed with thrust perpendicular or nearly perpendicular tothe roll and pitch axes of the vehicle, the vehicle also being providedwith means for controlling configured to control the thrusters and theircorresponding tilting mechanisms.
 2. The propulsion system according toclaim 1, further comprising two main thrusters, each placed laterallyfrom the roll axis of the vehicle and symmetrically and perpendicular tothe roll axis of the vehicle, and having one auxiliary thruster fixedand not tiltable, placed on or at close vicinity of an end of thevehicle roll axis, with thrust perpendicular or nearly perpendicular tothe roll and pitch axes of the vehicle.
 3. The propulsion systemaccording to claim 1, further comprising two main thrusters, each placedlaterally from the roll axis of the vehicle and symmetrically andperpendicular to the roll axis of the vehicle, and having two auxiliarythrusters, fixed and not tiltable, placed at or in close vicinity offront and rear ends of the roll axis of the vehicle, with thrustperpendicular or nearly perpendicular to the roll and pitch axes of thevehicle.
 4. The propulsion system according to claim 1, furthercomprising two main thrusters, each placed laterally from the roll axisof the vehicle and symmetrically and perpendicular to the roll axis ofthe vehicle, and having both auxiliary thrusters, fixed and nottiltable, placed at or in close vicinity of front or rear ends of thevehicle, with thrust perpendicular or nearly perpendicular to the rolland pitch axes of the vehicle.
 5. The propulsion system according toclaim 1, further comprising two main thrusters, wherein one of the mainthrusters is placed at or in close vicinity of the front end of thevehicle roll axes and the other of said main thrusters is placed at orin close vicinity of the rear end of the vehicle roll axis, the systemfurther comprising two auxiliary thrusters, each placed laterally fromthe roll axis of the vehicle, and symmetrically and perpendicularly tothe roll axis of the vehicle, the geometric center of said fixedthrusters arrangement being located at or in close vicinity of the masscenter of the vehicle, with thrust perpendicular or nearly perpendicularto the roll and pitch axes of the vehicle.
 6. The propulsion systemaccording to claim 1, wherein the thrusters are selected from thefollowing group: propellers, jets, fans, rockets, magnet thrusters,electric thrusters, turbines or any other propulsion system.
 7. Apropulsion process for a propulsion system of a vehicle, the system ableto move the vehicle along three independent translation axes and aroundthree independent rotation axes, wherein the propulsion system isconnected to the vehicle and the vehicle is able to move inside a fluidor vacuum with three independent translation axes movements and threeindependent rotation axes movements, the system comprising at least twomain thrusters, connected to the vehicle by means for attachingcomprising tilting mechanisms and means for joining, said tiltingmechanisms tilting the main thrusters around two axes, pitch and roll,independently from each other, wherein a geometric center of anarrangement of said tilting mechanisms is located at or in closevicinity of a mass center of the vehicle, and in that the systemcomprises at least one auxiliary thruster connected to the said vehicleby the means for joining, wherein the at least one auxiliary thrusterand the tilting mechanisms of the said main thrusters define ageometrical figure shaped, approximately, as an equilateral triangle oras a diamond, said triangle or diamond lying on a horizontal plan,defined by longitudinal (roll) and lateral (pitch) axes of the vehicle,the at least one auxiliary thruster and the tilting mechanisms of themain thrusters being disposed at apexes of said geometrical figure insuch a way that the geometrical center of said figure is disposed on alongitudinal axis of the vehicle, wherein the at least one auxiliarythruster is fixed with thrust perpendicular or nearly perpendicular tothe roll and pitch axes of the vehicle, the vehicle also being providedwith means for controlling configured to control the thrusters and theircorresponding tilting mechanisms, the process comprising: translationalmovements over the horizontal plan are achieved by tilting all the mainthrusters, around their tilt axes, which are perpendicular to theintended translational movement, and also by changing the global thrustof the thrusters in such a way as to maintain vehicle altitude;translational movement along a vertical axis is accomplished by havingall the main thrusters in a vertical tilt position, by increasing thethrust of all the thrusters so that their combined thrust is greaterthan a weight of the vehicle for it to ascend, and by reducing thethrust to less than the vehicle weight for the vehicle to descend;rotation around the vertical axis is accomplished by tilting the mainthrusters around the same axis connecting the tilting mechanisms, at anequal angle in modulus but with opposite signal of a main thruster inrelation to its opposed main thruster, and also by changing thethrusters overall thrust to maintain altitude; rotation around the axisdefined by the means for attaching of the tilting mechanisms of two mainthrusters is accomplished by varying the thrust in the auxiliarythruster(s), the main thrusters tilting in the opposite sense to that ofthe rotation of the vehicle and also by changing the thrust of thethrusters in order to maintain altitude; rotation around an axisorthogonal to the previous axis and the vertical axis is accomplished bya different thrust in the main thrusters and by tilting the same in thesense opposite to vehicle rotation and also by changing the thrust ofthe thrusters in order to maintain altitude; and wherein, when usingpropellers as thrusters, these being placed opposed to each other, thepropellers turning in opposite directions in order to compensate torqueover the vehicle.
 8. The propulsion process according to claim 7,wherein the system further comprises two main thrusters, each placedlaterally from the roll axis of the vehicle and symmetrically andperpendicular to the roll axis of the vehicle, and having one auxiliarythruster fixed and not tiltable, placed on or at close vicinity of anend of the vehicle roll axis, with thrust perpendicular or nearlyperpendicular to the roll and pitch axes of the vehicle, wherein theprocess further comprises: independent forward or backward motion isaccomplished by tilting the main thruster around the pitch axis at thesame angle (a), by increasing the thrust with equal value in boththrusters, in such a way that the vector sum of the vertical thrustequals the weight of the vehicle thus maintaining the altitude of theaircraft; independent lateral motion is accomplished by tilting the mainthrusters at the same angle(b1), around the roll axis, and by increasingthe thrust in such a way that the vector sum of the vertical thrustsequals the weight of the vehicle in order to maintain altitude;independent diagonal motion is accomplished by combining tilting of themain thrusters at the same angle (b1), around the roll and pitch axes,again with the increase of the thrust in such a way that the vector sumof the vertical thrust equals the weight of the vehicle thus maintainingaltitude; independent upward or downward motion is accomplished byassuming a vertical position of the main thrusters and by equallyincreasing the vertical thrust producing forces on the vertical axis(yaw) that can be greater or lesser than the weight of the vehicle;independent rotation around the yaw (vertical) axis is accomplished bytilting the main thrusters around the pitch axis (this axis being thesame connecting the tilting mechanisms of the main thrusters), at angles(c, d) that are equal in modulus but with opposite signal, and also byincreasing the thrust thus maintaining altitude; independent rotationaround the pitch axis of the vehicle is accomplished by using theauxiliary thruster thus creating a propulsive force by generating thruston the auxiliary thruster, this propulsive force being able to bedirected upward or downward, and when using propellers as thrusters, theupward or downward force is produced by two counter-rotated propellers,or by a single propeller rotating in two possible directions, or bypropeller pitch change maintaining the rotation direction, wherein, inorder for the vehicle to stay in the same spatial translational positionof the mass center, the main thrusters are tilted around the pitch axisat angles (g) and (e) in opposite direction to the vehicle rotation,these angles being the same if the auxiliary thruster does not generateany torque and different if they do, and the main thrusters change theirthrust to maintain the altitude; and independent rotation around theroll axis of the vehicle is accomplished by using different impulsiveforces of the main thrusters, wherein in order for the vehicle tomaintain the same spatial translational position of the mass center, themain thrusters are tilted around the roll axis in the opposite directionof the vehicle rotation, at equal angles (k, j) if there is no resultingtorque from the main thrusters, and if there is resulting torque, thenthe main thrusters are also tilted around the pitch axis with angles (q,o), in order to compensate the elevation of the axis connecting theauxiliary thrusters, and changing the main thrusters thrust thusmaintaining altitude.
 9. The propulsion process according to claim 7,wherein the system further comprises two main thrusters each placedlaterally from the roll axis of the vehicle and symmetrically andperpendicularly to the roll axis of the vehicle, wherein two auxiliarythrusters fixed and not tiltable, placed at or in close vicinity offront and rear ends of the roll axis of the vehicle, with thrustperpendicular or nearly perpendicular to the roll and pitch axes of thevehicle, wherein the process further comprises: independent motionforward or backward is accomplished by tilting the main thrusters aroundthe pitch axis at the same angle (a), by increasing the thrust withequal value in both thrusters, in such a way that the vector sum of thevertical thrust equals the weight, thus maintaining the altitude;independent lateral motion is accomplished by tilting the main thrustersat the same angle (b1), around the roll axis, and by increasing thethrust in such a way that the vector sum of the thrust equals the weightof the vehicle thus maintaining altitude; independent diagonal motion isaccomplished by combining tilting of the main thrusters around the rolland pitch axis, again with the increase of thrust in such a way that thevector sum of the vertical thrust equals the weight of the vehicle thusmaintaining altitude; independent upward or downward motion isaccomplished by assuming vertical position of the main thrusters and byincreasing equally the vertical thrust producing forces on the verticalaxis (yaw) that can be greater or lesser than the weight of the vehicle;independent rotation around the yaw (vertical) axis is accomplished bytilting the main thrusters around the pitch axis (this axis being thesame connecting the tilting mechanisms of the main thrusters), at angles(c, d) that are equal in modulus but with opposite signal, and also byincreasing the thrust thus maintaining altitude; independent rotationaround the pitch axis of the vehicle is accomplished using auxiliarythrusters with different thrusts, in such a way that for maintaining thesame spatial translational position of the mass center of the vehicle,the main thrusters are tilted around the pitch axis in the oppositedirection to that of the vehicle tilt, at angles (g) and (e), theseangles being equal if the auxiliary thrusters do not generate any torqueand different if they do, and the main thrusters changing their thrustthus maintaining the altitude; and independent rotation around the rollaxis of the vehicle is accomplished using different impulsive forces ofthe main thrusters, wherein, in order to maintain the same spatialtranslational position of the mass center of the vehicle, the mainthrusters are tilted around the roll axis in the opposite direction ofthe vehicle rotation, at angles (k, j) that are equal if there is noresulting torque from the main thrusters, and if there is resultingtorque, then the main thrusters are also tilted around the pitch axis atangles (q, o), it being necessary to change the main thrusters thrustthus maintaining altitude in order to compensate the elevation in theaxis connecting the auxiliary thrusters.
 10. The propulsion processaccording to claim 7, wherein the system further comprises two mainthrusters each placed laterally from the roll axis of the vehicle andsymmetrically and perpendicular to the roll axis of the vehicle, whereinboth auxiliary thrusters, fixed and not tiltable, are placed at or inclose vicinity of front and rear ends of the vehicle, with thrustperpendicular or nearly perpendicular to the roll and pitch axes of thevehicle, the process further comprising: independent forward or backwardmotion is accomplished by tilting the main thrusters around pitch axisat the same angle (a), by increasing the thrust with equal value in boththrusters, in such a way that the vector sum of all thruster equals theweight of the vehicle thus maintaining altitude; independent lateralmotion is accomplished by tilting the main thrusters at the same angle(b1) around the roll axis, and by increasing the thrust in such a waythe vector sum of the vertical thrust equals the weight of the vehiclethus maintaining altitude; independent diagonal motion is accomplishedby combining tilting of the main thrusters around the roll and pitchaxis, again with the increase of thrust in such a way that the vectorsum of the vertical thrusts equals the weight of the vehicle thusmaintaining altitude; independent upward or downward motion isaccomplished by assuming vertical position of the main thrusters and byincreasing equally the vertical thrust producing forces on the verticalaxis (yaw) that can be greater or lesser than the weight of the vehicle;independent rotation around the yaw (vertical) axis is accomplished bytilting the main thrusters around the pitch axis (this axis being thesame connecting the tilting mechanisms of the main thrusters), at angles(c, d) that are equal in modulus but with opposite signal, and also byincreasing the thrust thus maintaining altitude; independent rotationaround the pitch axis of the vehicle is accomplished by using oneauxiliary thrusters with thrust in the upward direction, perpendicularto the vehicle roll axis, or downward thrust in another auxiliarythruster, or vice versa, in such a way that for maintaining the samespatial translational position of the mass center of the vehicle, themain thrusters are tilted around the pitch axis in the oppositedirection to the vehicle tilt, at angles (g) and (e), these angles beingequal if the auxiliary thrusters do not generate any torque anddifferent if they do, and changing the main thrusters thrust thusmaintaining altitude; and independent rotation around the roll axis ofthe vehicle is accomplished using different impulsive forces of the mainthrusters, wherein in order for the vehicle to maintain the same spatialtranslational position of the mass center, the main thrusters are tiltedaround the roll axis in the opposite direction of the vehicle rotation,at equal angles (k, j) if there is no resulting torque from the mainthrusters, and if there is a resulting torque, then the main thrustersare also tilted around the pitch axis with angles (q, o), in order tocompensate the elevation of the axis connecting the auxiliary thrusters,and changing the main thrusters thrust thus maintaining altitude. 11.The propulsion process according to claim 7, for a system furthercomprising two main thrusters wherein one of said main thrusters isplaced at or in close vicinity of the front end of the vehicle roll axesand the other of said main thrusters is placed at or in close vicinityof the rear end of the roll axis of the vehicle, and further comprisingtwo auxiliary thrusters are each placed laterally from the roll axis ofthe vehicle, and symmetrically and perpendicularly to the roll axis ofthe vehicle, the geometric center of said fixed thrusters arrangementbeing located at or in close vicinity of the mass center of the vehicle,with thrust perpendicular or nearly perpendicular to the roll and pitchaxes of the vehicle, the process further comprising: independent motionforward or backward is accomplished by tilting the main thrusters aroundthe pitch axis at an equal angle (a), and by increasing the thrust usingequal value in both thrusters, in such a way that the vector sum of themain thrusters is the same as the weight of the vehicle, thusmaintaining the altitude of the aircraft; independent lateral motion isaccomplished by tilting the main thrusters or propellers equally at anangle (b1) around the roll axis, and simultaneously increasing thethrust, in such a way that the vector sum of the vertical thrust equalsthe weight of the vehicle thus maintaining altitude; independentdiagonal motion is accomplished by combining tilting of the mainthrusters around the roll and pitch axes, again with the increase ofthrust in such a way that the vector sum of the vertical thrust equalsthe weight of the vehicle thus maintaining altitude; independent upwardor downward motion is accomplished by assuming vertical position of themain thrusters and by increasing equally the vertical thrust producingforces on the vertical axis (yaw) that can be greater or lesser than theweight of the vehicle; independent rotation around the yaw (vertical)axis is accomplished by tilting of the main thrusters around the rollaxis, at equal angles in modulus, but with opposite signal, and also byincreasing the thrust thus maintaining altitude; independent rotationaround the pitch axis of the vehicle is accomplished by using the mainthrusters with different thrusts, in such a way that for maintaining thesame spatial translational position of the mass center of the vehicle,the main thrusters are tilted in the opposite direction to that of thevehicle tilt, at angles (g) and (e), these angles being equal if themain thrusters do not generate any torque and different if they do, andchanging the main thrusters thrust thus maintaining altitude; andindependent rotation around the roll axis of the vehicle is accomplishedusing different impulsive forces of the auxiliary thrusters, in such away that for the vehicle to maintain the same spatial translationalposition of the mass center, the main thrusters are tilted, around theroll axis, in the opposite direction of the vehicle rotation, at equalangles (q, o) that are equal if there is no resulting torque from themain thrusters, and if there is resulting torque, then the mainthrusters are also tilted around the pitch axis, being necessary tochange the auxiliary thrusters thrust for stabilizing the altitude inorder to compensate the elevation of the axis that connects theauxiliary thrusters.
 12. A propulsion process according to claim 11,wherein the direct electrical control of the actuators, in the event ofabsence of failure of the at least one controller is made in manual modeby using eight independent switches commuting the position of thecontroller output to manual output, the power of any thruster beingaltered by changing RPM (rotations per minute) or propeller pitch orthrust, the outputs for the control of the vehicle being the following:left main thruster power, right main thruster power, front auxiliarythruster power, rear auxiliary thruster power and, also, roll tilt ofleft main thruster and the pitch tilt of the left main thruster, rolltilt of the right main thruster and the pitch tilt of the right mainthruster; in which the power of the right main thruster will be equal tothe measured signal of the command of power subtracted to the measuredsignal of the command of roll rotation of the vehicle; the power of theleft main thruster will be equal to the measured power command signaladded to the measured rotation command signal of the vehicle around theroll axis; the power of the front auxiliary thruster will be themeasured power command signal plus the measured pitch rotation commandsignal of the vehicle around pitch axis; the power of the rear auxiliarythruster will be equal to the measured power command signal subtractedto the measured pitch rotation command signal; the signal of roll ofleft main thruster is given by the sum of the frontal translation signalwith the yaw rotation signal; the signal of right main thruster pitchtilt is given by the measured frontal translation signal subtracted tothe measured yaw rotation signal of the vehicle; and the roll rotationsignal of the left and right main thrusters are equal and are given bythe measured lateral translation signal, wherein any one of thesecommands can be affected by a multiplicative factor that can bedifferent for each one in order to improve the accuracy of the controlof the vehicle in the MANUAL mode.
 13. The propulsion process accordingto claim 7, wherein the electrical control of the actuators is done byat least one controller in a majority decision process that receivesinformation about: parameters of position of the roll axis, position ofthe yaw axis, position of the pitch axis, velocity in X (forward), in Y(sideways) and Z (up) and respective accelerations, pitch and roll tiltof the thrusters and their RPM or propeller pitch, and respectivethrusts and torque, the air speed, temperature, pressure, altitude, theforces internal resultant and torques acting on the vehicle; usercommands, and constantly calculating the actual mass center Cg, thecontrol algorithm being any one allowing the control in threeindependent translational axis (X, Y, and Z) and three independentrotational axis (rotation around X, Y, and Z), minimizing the externaldisturbances.
 14. The use of a propulsion system and propulsion processaccording to claim 7, in an aircraft with tandem wings placed at thefront and the back of the airplane wherein the front wing is lower thanrear wing (or the opposite) in such a way as to minimize the wingsinfluence on the propulsive airflow from the main thrusters in takeoffor in horizontal cruise, said main thrusters being able to tilt ninetydegrees or more around the pitch axis in order to allow the aircraft tobe a convertible, capable of flying like an aircraft in cruise flight,and as an “helicopter” in takeoff and landing, the wings overall liftforce being located at or in close vicinity of the Cg, the aircraft inthis configuration having a vertical stabilizer and a directional rudderthat can be used in coordination with the normal vector control, theaircraft being able to also have all the normal airplane controls. 15.The use of a propulsion system and propulsion process according to claim7, in an aircraft with wings placed similarly to conventional airplanes,near Cg, wherein the aircraft can be used like a convertible, in whichcase the control is done by the vector main and auxiliary thrusters andby the directional rudder, and it can also have all the control surfacesof a conventional airplane.
 16. The use of a propulsion system andpropulsion process according to claim 7 in a vehicle moving inside afluid or vacuum.
 17. The use of a propulsion system and propulsionprocess according to claim 7, in a toy, an UAV, a submarine vehicle, aROV or a spacecraft.